PIC16F18313 SSD1306 OLED test program xc8 source

pic_oled.c

// CONFIG1
#pragma config FEXTOSC = OFF    // FEXTOSC External Oscillator mode Selection bits (Oscillator not enabled)
#pragma config RSTOSC = HFINT32 // Power-up default value for COSC bits (HFINTOSC with 2x PLL (32MHz))
#pragma config CLKOUTEN = OFF   // Clock Out Enable bit (CLKOUT function is disabled; I/O or oscillator function on OSC2)
#pragma config CSWEN = ON       // Clock Switch Enable bit (Writing to NOSC and NDIV is allowed)
#pragma config FCMEN = ON       // Fail-Safe Clock Monitor Enable (Fail-Safe Clock Monitor is enabled)

// CONFIG2
#pragma config MCLRE = ON       // Master Clear Enable bit (MCLR/VPP pin function is MCLR; Weak pull-up enabled )
#pragma config PWRTE = OFF      // Power-up Timer Enable bit (PWRT disabled)
#pragma config WDTE = OFF       // Watchdog Timer Enable bits (WDT disabled; SWDTEN is ignored)
#pragma config LPBOREN = OFF    // Low-power BOR enable bit (ULPBOR disabled)
#pragma config BOREN = ON       // Brown-out Reset Enable bits (Brown-out Reset enabled, SBOREN bit ignored)
#pragma config BORV = LOW       // Brown-out Reset Voltage selection bit (Brown-out voltage (Vbor) set to 2.45V)
#pragma config PPS1WAY = ON     // PPSLOCK bit One-Way Set Enable bit (The PPSLOCK bit can be cleared and set only once; PPS registers remain locked after one clear/set cycle)
#pragma config STVREN = ON      // Stack Overflow/Underflow Reset Enable bit (Stack Overflow or Underflow will cause a Reset)
#pragma config DEBUG = OFF      // Debugger enable bit (Background debugger disabled)

// CONFIG3
#pragma config WRT = OFF        // User NVM self-write protection bits (Write protection off)
#pragma config LVP = ON         // Low Voltage Programming Enable bit (Low voltage programming enabled. MCLR/VPP pin function is MCLR. MCLRE configuration bit is ignored.)

// CONFIG4
#pragma config CP = OFF         // User NVM Program Memory Code Protection bit (User NVM code protection disabled)
#pragma config CPD = OFF        // Data NVM Memory Code Protection bit (Data NVM code protection disabled)

#include <xc.h>

#define _XTAL_FREQ 32000000UL
#define _I2C_FREQ 100000UL
#define OLED_ADRS 0x78

void i2c_init(void){
    ANSA0 = 0; // Desable analog
    TRISA0 = 1; // RA0 input
    WPUA0 = 1; // Week pullup
    RA0PPS = 0x19; // RA0->DAT1 out
    SSP1DATPPS = 0; // DAT1 in->RA0

    ANSA1 = 0; // Desable analog
    TRISA1 = 1; // RA1 input
    WPUA1 = 1; // Week pullup
    RA1PPS = 0x18; // RA1->CLK1 out
    SSP1CLKPPS = 1; // CLK1 in->RA1

    SSP1STAT = 0x00; // Clear status
    SSP1CON1 = 0x08; // I2C Master mode
    SSP1CON2 = 0x00; // Default I2C mode
    SSP1ADD  = _XTAL_FREQ / (4 * _I2C_FREQ) - 1; // Clock setting
    SSPEN = 1; // I2C enable
}

void i2c_start(void){
    SEN = 1; // Start condition
    while(SEN); // Wait for start
}

void i2c_stop(void){
    PEN = 1; // Stop condition
    while(PEN); // Wait for Stop
}

void i2c_write(unsigned char d){
    SSP1IF = 0; // Clear flag
    SSP1BUF = d; // Write
    while(!SSP1IF); // Wait for write done
}

void oled_init(){
    i2c_start();
    i2c_write(OLED_ADRS); // OLED slave address
    i2c_write(0x00); // Control byte Co=0, D/C=0
    i2c_write(0x8d); // Set charge pump
    i2c_write(0x14); // Enable charge pump
    i2c_write(0xaf); // Display ON
    i2c_stop();
}

void oled_pattern(void){
    unsigned int i;

    i2c_start();
    i2c_write(OLED_ADRS); // OLED slave address
    i2c_write(0x00); // Control byte Co=0, D/C=0
    i2c_write(0x20); // Set memory addressing mode
    i2c_write(0x00); // Horizontal addressing mode
    i2c_write(0x21); // Set column address
    i2c_write(0x00); // Column start address
    i2c_write(0x7f); // Column end address
    i2c_write(0x22); // Set page address
    i2c_write(0x00); // Page start address 0
    i2c_write(0x07); // Page end address 7
    i2c_stop();
    i2c_start();
    i2c_write(OLED_ADRS); // OLED slave address
    i2c_write(0x40); // Control byte Co=0, D/C=1
    for(i=0; i<512; i++){ // 128 x 8
        i2c_write(0x55); // fill pattern
        i2c_write(0xAA); // fill pattern
    }
    i2c_stop();
}

void main(void) {
    WPUA = 1; // Week pullups enable
    
    i2c_init(); // I2C initialize
    oled_init(); // OLED initialize
    oled_pattern(); // Fill pattern

    while(1);
}